1. Technical Field
The present invention relates to an optical position detection device that optically detects a position of a target object and equipment with position detection function including the optical position detection device.
2. Related Art
As an optical position detection device that optically detects a position of a target object, for example, a device in which detection lights are output from two detection light source units via a light-transmissive member toward the target object and the detection lights reflected by the target object are transmitted through the light-transmissive member and detected in a light detection unit has been suggested. In the optical position detection device, for example, on the basis of a result of a differential operation between the two detection light source units according to a detection result in the light detection unit, a ratio of a distance between one detection light source unit of the two detection light source units and the target object to a distance between the other detection light source unit and the target object is obtained, and the one-dimensional coordinate in a direction in which the two detection light source units are separated (see Patent Document 1 (JP-T-2003-534554)).
In application of the configuration described in Patent Document 1, two-dimensional coordinates may be detected by adding two detection light source units in a direction crossing the direction in which the two detection light source units are separated. However, in the case of the configuration for detection of two-dimensional coordinates by application of the configuration described in Patent Document 1, four detection light source units are necessary and the cost and the size of the optical position detection device are increased. Further, in the case where the differential operation between the detection light source units is used for obtaining two-dimensional coordinates, only the position of the target object within a region surrounded by the detection light source units or in a peripheral region thereof may be detected, and there is a problem that the detection range is smaller despite a large number of detection light source units.